The invention relates to a levelling ram for roof-shield mine support systems in which at least two such levelling rams are provided in each case between a shield frame unit and an associated gap-seal plate which is arranged slidably relative to the associated shield frame in a transverse direction relative to the direction of forepoling.
The levelling ram for roof-shield mine support systems, to which the present invention is directed, is generally disclosed in British Pat. Nos. 1,054,651 and 1,134,552, and in German Pat. No. 22 10 757, respectively as aligning cylinders 27, 28 and 10, 11, and 19. The frame units and gap seal plates, with which the levelling rams are associated as described herein, are likewise generally disclosed in these patents.